Controlling device



Dec. 10, 1940. F. M. SLATER CONTROLLING DEVICE Filed May 2, 1940 r a Pm T m8. MM m r F HIS ATTORNEY Patented Dec. 10, 1940 UNITED STATES PATENT OFFICE CONTROLLING DEVICE Application May 2, 1940, Serial No. 332,895

11 Claims.

This invention relates to rock drilling mechanisms, and more particularly to a controlling device for the feeding mechanism of a rock drill.

One object of the invention is to eifect the automatic control of the pressure fluid supply to the feeding mechanism in the various posi tions of operation of the drilling mechanism with respect to the work.

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification and in which similar reference numerals refer to similar parts,

Figure 1 is a longitudinal view, partly broken away, of a rock drilling mechanism equipped with a controlling device constructed in accordance with the practice of the invention,

Figure 2 is a transverse view taken through Figure 1 on the line 2-2,

Figures 3, 4 and 5 are transverse views taken through Figure 2 on the line 3-3, showing the controlling device in different controlling positions, and

Figure 6 is a perspective view of a detail.

Referring more particularly to the drawing, the drilling mechanism, designated in genera1 by comprises a rock drill 2! for actuating a working implement 22 and a feeding mechanism 23 for advancing and retracting the rock drill El 30 toward and from the work.

The rock drill may be of a conventional fluid actuated percussive type of which the cylinder 24 and front and back heads 25 and 26 form the casing parts and are clamped together by side rods 2'! arranged on opposite sides of the rock rill. The front'head 25 serves as a guide for the working implement 22, and in the back head 23 is a throttle valve, only the lever 28 of which is shown, for controlling communication between 40 pressure fluid supply and the drilling mechanism.

The feeding mechanism 23 is arranged on the side of the rock drill 2! and comprises a feeding cylinder 29 having a lug 30 intermediate its ends seating against the rear end of the back head 26, and bolts 3| in the lug 30 secure the feeding cylinder to the back head. The feeding The shell 36 is of suitable length to serve as a guide for the cylinder 29 and has the usual cone 3! for engagement with clamping mechanism (not shown) commonly used for securing drilling mechanisms'of this type to a support. On 5 the front end of the shell 36 is an up-turned portion 38 to which is affixed, as by a nut 39, .a rod 40 extending into the cylinder 29 and having a piston 4| on its opposite end.

In the arrangement shown the throttle valve of the rock'drill controls communication between pressure fluid supply and the rock drill 2| and the feeding mechanism 23 and also controls communication between the feeding mechanism and the atmosphere. The back head 26 is accordingly provided with a pair of passages t2 and 23 that lead from the throttle Valvefor supplying pressure fluid to the front and back ends, respectively, of the feeding cylinder 29, a tube it on the feeding cylinder 29 serving as an extension of the passage 43 to the rear end of the feeding cylinder.

The passage 43 leads directly to the rear end of the cylinder 29 and is controlled only by the throttle valve. The passage 42, on the other hand, leads to a control chamber 45 in the lower part of the back head and leading from the control chamber 45 is an inlet passage 48 that extends through the back head and the cylinder 2 and communicates with the front end of the feeding cylinder 29 through a conduit ll suitably attached to the cylinders 24 and 29.

The recess forming the control chamber 15 is shown as extending from one side of the back head 26 to the other. Its ends are sealed by plugs 4-8 and 49 held securely in sealing position by a bolt 5!] extending through both plugs and axially of the chamber 45. In the form of the invention illustrated the passage 52 also extends through the plug 49 and the bolt 50 and has a pair of outlet openings 5! to afford communication between the passage 52 and the control chamber 45. The outlet openings are located in the horizontal plane of the bolt 52 and open on the same side of the bolt, preferably near the ends of the control chamber.

'In the same transverse planes as the outlet openings 5|, and in the wall of the control chamber are groups of passages 52 that con erably the control chamber 45 is provided with 555 an atmospheric vent 54, of small flow area, to afford constant communication between the atmosphere and a point in the control chamber opposite the inlet passage 46.

5 The shaft 55, which lies at right angles to the feeding mechanism 23, acts as a bearing for a pendulum member 55 freely swingable on the shaft to control the various passages opening into the control chamber 45. The pendulum member 55 is somewhat shorter than the control chamber so that pressure fluid may flow between the end surfaces of the two.

In the ends of the pendulum 55 are recesses 56 that extend inwardly beyond the outlet openings 15 and are arranged eccentrically with respect to the portions of the shaft 50 lying within the recesses. Thus, the side walls 51 of the recesses overlie the outlet openings 5| and may serve to control the flow of pressure fluid from the said 20 outlet openings. The walls 51 are so located, however, that they do not contact at any point with the surface of the shaft 50 and pressure fluid may, therefore, issue from the outlet openings in all positions of the pendulum member.

25 The pendulum member also controls the passages 52 and the atmospheric vent 54. To this end the depending weight portion 58 of said member is flared to a width enabling it to simultaneously overlie all of the passages 52, and

a slight degree of clearance 59 exists between the peripheral surface 60 of the member and the wall of the chamber 45. 1

In practice the device operates as follows: Whenever it is intended to operate the drilling mechanism the throttle valve of the rock drill is moved into position to admit pressure fluid to the rock drill 2| and the supply passage 42. The pressure fluid admitted to the passage 42 passes through the recesses 56 into the chamber 45, thence through the passage 46 into the front end of the feeding cylinder 29 to move the rock drill 2| forwardly toward the work.

In the horizontal vposition of the drilling mechanism, as shown in Figures 1, 2 and 3, neither the passages 52 nor the vent 54 will be covered by the weight portion 58 of the pendulum and the portions of the walls 51 of the recess 56 confronting the outlet openings 5| are suitably spaced with respect thereto to assure an ample supply of pressure fluid to the feeding cylinder. This is desirable for the reason that, in this position of the drilling mechanism, all the force applied to it for maintaining the rock drill in 55 the correct operative relationship with the working implement must be supplied by the pressure fluid in the cylinder 29 since no assistance will be derived from the weight of the rock as in the case of drilling a downwardly inclined hole.

60 When the feeding mechanism reaches the forward limit of its feeding movement the throttle valve of the rock drill is rotated to another controlling position to open the passage 42 to the atmosphere and to communicate the passage 43 65 with pressure fluid supply. Pressure fluid will then be exhausted from the front end of the feeding cylinder 29 and pressure fluid will flow into the rearend of the feeding cylinder 29 to retract the rock drill.

70 In operationsrequiring the drilling mechanism to point downwardly, as when drilling down holes certain or all of the passages 52 will lie beneath the surface 60 of the weight portion 58. The passage of pressure fluid into the front end 75 of the feeding cylinder 29 will then be restricted quite considerably and. the rock drill will descend toward the work mainly by gravity.

In these relative positions of the rock drill and the pendulum member the admission of pressure fluid into the chamber 45 will be reduced to a 5 minimum by the portions of the walls 51 of the recesses 56 nearest the axis of the shaft 50 which will then overlie the outlet openings 5|, and, inasmuch as the chamber 45 is then open to the atmosphere through the vent 54 very little, if any, pressure fluid will enter the front end of the feeding cylinder.

If, on the other hand, it be intended to feed the rock drill upwardly, for drilling up holes, the position which the drilling mechanism must occupy brings the passages 52 above the pendulum member, places the points in the walls 51 of the recesses 56' of maximum distance from the axis of the shaft directly above the outlet openings 5| and positions the vent 54 beneath the weight portion 58 of the pendulum member. The front end of the feeding cylinder will then receive an unrestricted supply of pressure fluid for feeding the rock drill toward the work since all the supply passages will be fully uncovered and only an inconsequential amount of pressure fluid may escape through the space 59 to the vent 54.

I claim:

1. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, and means acting automatically for controlling the pressure fluid supply to the feeding mechanism accordingly as the feeding mechanism is rotated about the axis of said means.

2. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor,

a passage for conveying pressure fluid to'the feeding mechanism and a pendulum member for controlling the passage.

3. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor,

a passage for conveying pressure fluid to the feeding mechanism, and a pendulum member swingable through the longitudinal plane of the feeding mechanism for controlling the passage.

4. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor,

a passage for conveying pressure fluid to the feeding mechanism, and a pendulum member for controlling the flow of pressure fluid from supply to the passage.

5. A controlling device, comprising a motor, a fluid actuated feeding mechanism'for the motor, means having a recess forming a chamber, a supply passage for pressure fluid opening into the chamber, a passage for conveying pressure fluid from the chamber to the feeding mechanism, and a pendulum member in the chamber to control both passages.

6. A controlling device, comprising a motor, a 60 fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a shaft in the chamber having a supply passage for pressure fluid, a pendulum member on the shaft to control the flow of pressure fluid from 6 the supply passage into the chamber, and a passage for conveying pressure fluid from the chamber to the feeding mechanism.

'7. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a sup ply passage for pressure fluid opening into the chamber, a passage leading from the chamber to the feeding mechanism, and a pendulum member in the chamber having portions to control the points of communication of the passages with the chamber.

8. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a supply passage for pressure fluid opening into the chamber, a pendulum member rotatable in the chamber having means to vary the area of communication between the supply passage, and a passage for conveying pressure fluid from the chamber to the feeding mechanism.

9. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a shaft in the chamber having a supply passage for pressure fluid opening into the chamber, a pendulum member in the chamber on the shaft having means overlying the outlet opening of the supply passage to vary the area of communication between the supply passage and the chamher, and a passage for conveying pressure fluid from the chamber to the feeding mechanism.

10. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a shaft in the chamber having a supply passage for pressure fluid opening into the chamber, a pendulum member in the chamber on the shaft suing from the supply passage to the chamber and a wall of said recess being arranged eccentrically with respect to the outlet opening of the supply passage to vary the flow of pressure fluid from the supply passage, and a passage for conveying pressure fluid from the chamber to the feeding mechanism.

11. A controlling device, comprising a motor, a fluid actuated feeding mechanism for the motor, means having a recess forming a chamber, a shaft in the chamber having a supply passage for pressure fluid and a plurality of outlet openings in the side of the shaft for the supply passage, a pendulum member in the chamber on the shaft having recesses in the planes of the outlet openings to convey pressure fluid from the outlet openings to the chamber and the walls of said recesses being arranged eccentrically with respect to the shaft to vary the flow of pressure fluid from the outlet openings, a passage for conveying pressure fluid to the feeding mechanism and having a plurality of inlet openings in communication with the chamber, and means on the pendulum member to restrict the flowof pressure fluid from the chamber into the inlet openings.

FRED M. SLATER. 

